static int generate(char id[34]) {
int fd;
char buf[16];
char *p, *q;
ssize_t k;
assert(id);
/* First, try reading the D-Bus machine id, unless it is a symlink */
if ((fd = open("/var/lib/dbus/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW)) >= 0) {
k = loop_read(fd, id, 33, false);
close_nointr_nofail(fd);
if (k >= 32) {
id[32] = '\n';
id[33] = 0;
log_info("Initializing machine ID from D-Bus machine ID.");
return 0;
}
}
/* If that didn't work, generate a random machine id */
if ((fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY)) < 0) {
log_error("Failed to open /dev/urandom: %m");
return -errno;
}
k = loop_read(fd, buf, sizeof(buf), false);
close_nointr_nofail(fd);
if (k != sizeof(buf)) {
log_error("Failed to read /dev/urandom: %s", strerror(k < 0 ? -k : EIO));
return k < 0 ? (int) k : -EIO;
}
for (p = buf, q = id; p < buf + sizeof(buf); p++, q += 2) {
q[0] = hexchar(*p >> 4);
q[1] = hexchar(*p & 15);
}
id[32] = '\n';
id[33] = 0;
log_info("Initializing machine ID from random generator.");
return 0;
}
_public_ int sd_id128_randomize(sd_id128_t *ret) {
_cleanup_close_ int fd = -1;
sd_id128_t t;
ssize_t k;
assert_return(ret, -EINVAL);
fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (fd < 0)
return -errno;
k = loop_read(fd, &t, 16, false);
if (k < 0)
return (int) k;
if (k != 16)
return -EIO;
/* Turn this into a valid v4 UUID, to be nice. Note that we
* only guarantee this for newly generated UUIDs, not for
* pre-existing ones.*/
*ret = make_v4_uuid(t);
return 0;
}
static int automount_dispatch_io(sd_event_source *s, int fd, uint32_t events, void *userdata) {
union autofs_v5_packet_union packet;
Automount *a = AUTOMOUNT(userdata);
ssize_t l;
int r;
assert(a);
assert(fd == a->pipe_fd);
if (events != EPOLLIN) {
log_error_unit(UNIT(a)->id, "Got invalid poll event on pipe.");
goto fail;
}
l = loop_read(a->pipe_fd, &packet, sizeof(packet), true);
if (l != sizeof(packet)) {
log_error_unit(UNIT(a)->id, "Invalid read from pipe: %s", l < 0 ? strerror(-l) : "short read");
goto fail;
}
switch (packet.hdr.type) {
case autofs_ptype_missing_direct:
if (packet.v5_packet.pid > 0) {
_cleanup_free_ char *p = NULL;
get_process_comm(packet.v5_packet.pid, &p);
log_info_unit(UNIT(a)->id,
"Got automount request for %s, triggered by "PID_FMT" (%s)",
a->where, packet.v5_packet.pid, strna(p));
} else
log_debug_unit(UNIT(a)->id, "Got direct mount request on %s", a->where);
r = set_ensure_allocated(&a->tokens, trivial_hash_func, trivial_compare_func);
if (r < 0) {
log_error_unit(UNIT(a)->id, "Failed to allocate token set.");
goto fail;
}
r = set_put(a->tokens, UINT_TO_PTR(packet.v5_packet.wait_queue_token));
if (r < 0) {
log_error_unit(UNIT(a)->id, "Failed to remember token: %s", strerror(-r));
goto fail;
}
automount_enter_runnning(a);
break;
default:
log_error_unit(UNIT(a)->id, "Received unknown automount request %i", packet.hdr.type);
break;
}
return 0;
fail:
automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);
return 0;
}
_public_ int sd_id128_get_boot(sd_id128_t *ret) {
static __thread sd_id128_t saved_boot_id;
static __thread bool saved_boot_id_valid = false;
_cleanup_close_ int fd = -1;
char buf[36];
ssize_t k;
unsigned j;
sd_id128_t t;
char *p;
if (!ret)
return -EINVAL;
if (saved_boot_id_valid) {
*ret = saved_boot_id;
return 0;
}
fd = open("/proc/sys/kernel/random/boot_id", O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (fd < 0)
return -errno;
k = loop_read(fd, buf, 36, false);
if (k < 0)
return (int) k;
if (k != 36)
return -EIO;
for (j = 0, p = buf; j < 16; j++) {
int a, b;
if (p >= buf + k)
return -EIO;
if (*p == '-')
p++;
a = unhexchar(p[0]);
b = unhexchar(p[1]);
if (a < 0 || b < 0)
return -EIO;
t.bytes[j] = a << 4 | b;
p += 2;
}
saved_boot_id = t;
saved_boot_id_valid = true;
*ret = t;
return 0;
}
void SopoMygga::loopRead() {
int r;
qDebug("LR");
m_notifier_write->setEnabled(true);
r=loop_read();
if (r!=MOSQ_ERR_SUCCESS) {
qWarning() << "Read fail " << r;
}
}
int loop_read_exact(int fd, void *buf, size_t nbytes, bool do_poll) {
ssize_t n;
n = loop_read(fd, buf, nbytes, do_poll);
if (n < 0)
return (int) n;
if ((size_t) n != nbytes)
return -EIO;
return 0;
}
int id128_read_fd(int fd, Id128Format f, sd_id128_t *ret) {
char buffer[36 + 2];
ssize_t l;
assert(fd >= 0);
assert(f < _ID128_FORMAT_MAX);
/* Reads an 128bit ID from a file, which may either be in plain format (32 hex digits), or in UUID format, both
* optionally followed by a newline and nothing else. ID files should really be newline terminated, but if they
* aren't that's OK too, following the rule of "Be conservative in what you send, be liberal in what you
* accept". */
l = loop_read(fd, buffer, sizeof(buffer), false); /* we expect a short read of either 32/33 or 36/37 chars */
if (l < 0)
return (int) l;
if (l == 0) /* empty? */
return -ENOMEDIUM;
switch (l) {
case 33: /* plain UUID with trailing newline */
if (buffer[32] != '\n')
return -EINVAL;
/* fall through */
case 32: /* plain UUID without trailing newline */
if (f == ID128_UUID)
return -EINVAL;
buffer[32] = 0;
break;
case 37: /* RFC UUID with trailing newline */
if (buffer[36] != '\n')
return -EINVAL;
/* fall through */
case 36: /* RFC UUID without trailing newline */
if (f == ID128_PLAIN)
return -EINVAL;
buffer[36] = 0;
break;
default:
return -EINVAL;
}
return sd_id128_from_string(buffer, ret);
}
_public_ int sd_id128_get_machine(sd_id128_t *ret) {
static __thread sd_id128_t saved_machine_id;
static __thread bool saved_machine_id_valid = false;
_cleanup_close_ int fd = -1;
char buf[33];
ssize_t k;
unsigned j;
sd_id128_t t;
if (!ret)
return -EINVAL;
if (saved_machine_id_valid) {
*ret = saved_machine_id;
return 0;
}
fd = open("/etc/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (fd < 0)
return -errno;
k = loop_read(fd, buf, 33, false);
if (k < 0)
return (int) k;
if (k != 33)
return -EIO;
if (buf[32] !='\n')
return -EIO;
for (j = 0; j < 16; j++) {
int a, b;
a = unhexchar(buf[j*2]);
b = unhexchar(buf[j*2+1]);
if (a < 0 || b < 0)
return -EIO;
t.bytes[j] = a << 4 | b;
}
saved_machine_id = t;
saved_machine_id_valid = true;
*ret = t;
return 0;
}
static void do_journal_append(char *file)
{
struct iovec iovec[5];
int r, f, j = 0;
ssize_t n;
_cleanup_free_ char *bootchart_file = NULL, *bootchart_message = NULL,
*p = NULL;
bootchart_file = strappend("BOOTCHART_FILE=", file);
if (bootchart_file)
IOVEC_SET_STRING(iovec[j++], bootchart_file);
IOVEC_SET_STRING(iovec[j++], "MESSAGE_ID=9f26aa562cf440c2b16c773d0479b518");
IOVEC_SET_STRING(iovec[j++], "PRIORITY=7");
bootchart_message = strjoin("MESSAGE=Bootchart created: ", file, NULL);
if (bootchart_message)
IOVEC_SET_STRING(iovec[j++], bootchart_message);
p = malloc(9 + BOOTCHART_MAX);
if (!p) {
r = log_oom();
return;
}
memcpy(p, "BOOTCHART=", 10);
f = open(file, O_RDONLY);
if (f < 0) {
log_error("Failed to read bootchart data: %m\n");
return;
}
n = loop_read(f, p + 10, BOOTCHART_MAX, false);
if (n < 0) {
log_error("Failed to read bootchart data: %s\n", strerror(-n));
close(f);
return;
}
close(f);
iovec[j].iov_base = p;
iovec[j].iov_len = 10 + n;
j++;
r = sd_journal_sendv(iovec, j);
if (r < 0)
log_error("Failed to send bootchart: %s", strerror(-r));
}
static int do_journal_append(char *file) {
_cleanup_free_ char *bootchart_message = NULL;
_cleanup_free_ char *bootchart_file = NULL;
_cleanup_free_ char *p = NULL;
_cleanup_close_ int fd = -1;
struct iovec iovec[5];
int r, j = 0;
ssize_t n;
bootchart_file = strappend("BOOTCHART_FILE=", file);
if (!bootchart_file)
return log_oom();
IOVEC_SET_STRING(iovec[j++], bootchart_file);
IOVEC_SET_STRING(iovec[j++], "MESSAGE_ID=9f26aa562cf440c2b16c773d0479b518");
IOVEC_SET_STRING(iovec[j++], "PRIORITY=7");
bootchart_message = strjoin("MESSAGE=Bootchart created: ", file, NULL);
if (!bootchart_message)
return log_oom();
IOVEC_SET_STRING(iovec[j++], bootchart_message);
p = malloc(10 + BOOTCHART_MAX);
if (!p)
return log_oom();
memcpy(p, "BOOTCHART=", 10);
fd = open(file, O_RDONLY|O_CLOEXEC);
if (fd < 0)
return log_error_errno(errno, "Failed to open bootchart data \"%s\": %m", file);
n = loop_read(fd, p + 10, BOOTCHART_MAX, false);
if (n < 0)
return log_error_errno(n, "Failed to read bootchart data: %m");
iovec[j].iov_base = p;
iovec[j].iov_len = 10 + n;
j++;
r = sd_journal_sendv(iovec, j);
if (r < 0)
log_error_errno(r, "Failed to send bootchart: %m");
return 0;
}
int main(int argc, char* argv[]) {
int r, j = 0;
_cleanup_free_ char *p = NULL;
ssize_t n;
pid_t pid;
uid_t uid;
gid_t gid;
struct iovec iovec[14];
_cleanup_free_ char *core_pid = NULL, *core_uid = NULL, *core_gid = NULL, *core_signal = NULL,
*core_timestamp = NULL, *core_comm = NULL, *core_exe = NULL, *core_unit = NULL,
*core_session = NULL, *core_message = NULL, *core_cmdline = NULL, *t = NULL;
prctl(PR_SET_DUMPABLE, 0);
if (argc != _ARG_MAX) {
log_set_target(LOG_TARGET_JOURNAL_OR_KMSG);
log_open();
log_error("Invalid number of arguments passed from kernel.");
r = -EINVAL;
goto finish;
}
r = parse_pid(argv[ARG_PID], &pid);
if (r < 0) {
log_set_target(LOG_TARGET_JOURNAL_OR_KMSG);
log_open();
log_error("Failed to parse PID.");
goto finish;
}
if (cg_pid_get_unit(pid, &t) >= 0) {
if (streq(t, SPECIAL_JOURNALD_SERVICE)) {
/* Make sure we don't make use of the journal,
* if it's the journal which is crashing */
log_set_target(LOG_TARGET_KMSG);
log_open();
r = divert_coredump();
goto finish;
}
core_unit = strappend("COREDUMP_UNIT=", t);
} else if (cg_pid_get_user_unit(pid, &t) >= 0)
core_unit = strappend("COREDUMP_USER_UNIT=", t);
if (core_unit)
IOVEC_SET_STRING(iovec[j++], core_unit);
/* OK, now we know it's not the journal, hence make use of
* it */
log_set_target(LOG_TARGET_JOURNAL_OR_KMSG);
log_open();
r = parse_uid(argv[ARG_UID], &uid);
if (r < 0) {
log_error("Failed to parse UID.");
goto finish;
}
r = parse_gid(argv[ARG_GID], &gid);
if (r < 0) {
log_error("Failed to parse GID.");
goto finish;
}
core_pid = strappend("COREDUMP_PID=", argv[ARG_PID]);
if (core_pid)
IOVEC_SET_STRING(iovec[j++], core_pid);
core_uid = strappend("COREDUMP_UID=", argv[ARG_UID]);
if (core_uid)
IOVEC_SET_STRING(iovec[j++], core_uid);
core_gid = strappend("COREDUMP_GID=", argv[ARG_GID]);
if (core_gid)
IOVEC_SET_STRING(iovec[j++], core_gid);
core_signal = strappend("COREDUMP_SIGNAL=", argv[ARG_SIGNAL]);
if (core_signal)
IOVEC_SET_STRING(iovec[j++], core_signal);
core_comm = strappend("COREDUMP_COMM=", argv[ARG_COMM]);
if (core_comm)
IOVEC_SET_STRING(iovec[j++], core_comm);
#ifdef HAVE_LOGIND
if (sd_pid_get_session(pid, &t) >= 0) {
core_session = strappend("COREDUMP_SESSION=", t);
free(t);
if (core_session)
IOVEC_SET_STRING(iovec[j++], core_session);
}
#endif
if (get_process_exe(pid, &t) >= 0) {
core_exe = strappend("COREDUMP_EXE=", t);
free(t);
if (core_exe)
IOVEC_SET_STRING(iovec[j++], core_exe);
}
if (get_process_cmdline(pid, 0, false, &t) >= 0) {
core_cmdline = strappend("COREDUMP_CMDLINE=", t);
free(t);
if (core_cmdline)
IOVEC_SET_STRING(iovec[j++], core_cmdline);
}
core_timestamp = strjoin("COREDUMP_TIMESTAMP=", argv[ARG_TIMESTAMP], "000000", NULL);
if (core_timestamp)
IOVEC_SET_STRING(iovec[j++], core_timestamp);
IOVEC_SET_STRING(iovec[j++], "MESSAGE_ID=fc2e22bc6ee647b6b90729ab34a250b1");
IOVEC_SET_STRING(iovec[j++], "PRIORITY=2");
core_message = strjoin("MESSAGE=Process ", argv[ARG_PID], " (", argv[ARG_COMM], ") dumped core.", NULL);
if (core_message)
IOVEC_SET_STRING(iovec[j++], core_message);
/* Now, let's drop privileges to become the user who owns the
* segfaulted process and allocate the coredump memory under
* his uid. This also ensures that the credentials journald
* will see are the ones of the coredumping user, thus making
* sure the user himself gets access to the core dump. */
if (setresgid(gid, gid, gid) < 0 ||
setresuid(uid, uid, uid) < 0) {
log_error("Failed to drop privileges: %m");
r = -errno;
goto finish;
}
p = malloc(9 + COREDUMP_MAX);
if (!p) {
r = log_oom();
goto finish;
}
memcpy(p, "COREDUMP=", 9);
n = loop_read(STDIN_FILENO, p + 9, COREDUMP_MAX, false);
if (n < 0) {
log_error("Failed to read core dump data: %s", strerror(-n));
r = (int) n;
goto finish;
}
iovec[j].iov_base = p;
iovec[j].iov_len = 9 + n;
j++;
r = sd_journal_sendv(iovec, j);
if (r < 0)
log_error("Failed to send coredump: %s", strerror(-r));
finish:
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}
int main(int argc, char *argv[]) {
int seed_fd = -1, random_fd = -1;
int ret = EXIT_FAILURE;
void* buf;
size_t buf_size = 0;
ssize_t r;
FILE *f;
if (argc != 2) {
log_error("This program requires one argument.");
return EXIT_FAILURE;
}
log_set_target(LOG_TARGET_AUTO);
log_parse_environment();
log_open();
umask(0022);
/* Read pool size, if possible */
if ((f = fopen("/proc/sys/kernel/random/poolsize", "re"))) {
if (fscanf(f, "%zu", &buf_size) > 0) {
/* poolsize is in bits on 2.6, but we want bytes */
buf_size /= 8;
}
fclose(f);
}
if (buf_size <= POOL_SIZE_MIN)
buf_size = POOL_SIZE_MIN;
if (!(buf = malloc(buf_size))) {
log_error("Failed to allocate buffer.");
goto finish;
}
if (mkdir_parents_label(RANDOM_SEED, 0755) < 0) {
log_error("Failed to create directories parents of %s: %m", RANDOM_SEED);
goto finish;
}
/* When we load the seed we read it and write it to the device
* and then immediately update the saved seed with new data,
* to make sure the next boot gets seeded differently. */
if (streq(argv[1], "load")) {
if ((seed_fd = open(RANDOM_SEED, O_RDWR|O_CLOEXEC|O_NOCTTY|O_CREAT, 0600)) < 0) {
if ((seed_fd = open(RANDOM_SEED, O_RDONLY|O_CLOEXEC|O_NOCTTY)) < 0) {
log_error("Failed to open random seed: %m");
goto finish;
}
}
if ((random_fd = open("/dev/urandom", O_RDWR|O_CLOEXEC|O_NOCTTY, 0600)) < 0) {
if ((random_fd = open("/dev/urandom", O_WRONLY|O_CLOEXEC|O_NOCTTY, 0600)) < 0) {
log_error("Failed to open /dev/urandom: %m");
goto finish;
}
}
if ((r = loop_read(seed_fd, buf, buf_size, false)) <= 0) {
if (r != 0)
log_error("Failed to read seed file: %m");
} else {
lseek(seed_fd, 0, SEEK_SET);
if ((r = loop_write(random_fd, buf, (size_t) r, false)) <= 0)
log_error("Failed to write seed to /dev/urandom: %s",
r < 0 ? strerror(errno) : "short write");
}
} else if (streq(argv[1], "save")) {
if ((seed_fd = open(RANDOM_SEED, O_WRONLY|O_CLOEXEC|O_NOCTTY|O_CREAT, 0600)) < 0) {
log_error("Failed to open random seed: %m");
goto finish;
}
if ((random_fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY)) < 0) {
log_error("Failed to open /dev/urandom: %m");
goto finish;
}
} else {
log_error("Unknown verb %s.", argv[1]);
goto finish;
}
/* This is just a safety measure. Given that we are root and
* most likely created the file ourselves the mode and owner
* should be correct anyway. */
fchmod(seed_fd, 0600);
fchown(seed_fd, 0, 0);
if ((r = loop_read(random_fd, buf, buf_size, false)) <= 0)
log_error("Failed to read new seed from /dev/urandom: %s", r < 0 ? strerror(errno) : "EOF");
else {
if ((r = loop_write(seed_fd, buf, (size_t) r, false)) <= 0)
log_error("Failed to write new random seed file: %s", r < 0 ? strerror(errno) : "short write");
}
ret = EXIT_SUCCESS;
finish:
if (random_fd >= 0)
close_nointr_nofail(random_fd);
if (seed_fd >= 0)
close_nointr_nofail(seed_fd);
free(buf);
return ret;
}
int decompress_stream_lz4(int fdf, int fdt, off_t max_bytes) {
#ifdef HAVE_LZ4
_cleanup_free_ char *buf = NULL, *out = NULL;
size_t buf_size = 0;
LZ4_streamDecode_t lz4_data = {};
le32_t header;
size_t total_in = sizeof(header), total_out = 0;
assert(fdf >= 0);
assert(fdt >= 0);
out = malloc(4*LZ4_BUFSIZE);
if (!out)
return log_oom();
for (;;) {
ssize_t n, m;
int r;
n = read(fdf, &header, sizeof(header));
if (n < 0)
return -errno;
if (n != sizeof(header))
return errno ? -errno : -EIO;
m = le32toh(header);
if (m == 0)
break;
/* We refuse to use a bigger decompression buffer than
* the one used for compression by 4 times. This means
* that compression buffer size can be enlarged 4
* times. This can be changed, but old binaries might
* not accept buffers compressed by newer binaries then.
*/
if (m > LZ4_COMPRESSBOUND(LZ4_BUFSIZE * 4)) {
log_error("Compressed stream block too big: %zd bytes", m);
return -EBADMSG;
}
total_in += sizeof(header) + m;
if (!GREEDY_REALLOC(buf, buf_size, m))
return log_oom();
errno = 0;
n = loop_read(fdf, buf, m, false);
if (n < 0)
return n;
if (n != m)
return errno ? -errno : -EIO;
r = LZ4_decompress_safe_continue(&lz4_data, buf, out, m, 4*LZ4_BUFSIZE);
if (r <= 0)
log_error("LZ4 decompression failed.");
total_out += r;
if (max_bytes != -1 && total_out > (size_t) max_bytes) {
log_debug("Decompressed stream longer than %zd bytes", max_bytes);
return -EFBIG;
}
n = loop_write(fdt, out, r, false);
if (n < 0)
return n;
}
log_debug("LZ4 decompression finished (%zu -> %zu bytes, %.1f%%)",
total_in, total_out,
(double) total_out / total_in * 100);
return 0;
#else
log_error("Cannot decompress file. Compiled without LZ4 support.");
return -EPROTONOSUPPORT;
#endif
}
int main(int argc, char *argv[]) {
_cleanup_close_ int seed_fd = -1, random_fd = -1;
bool read_seed_file, write_seed_file;
_cleanup_free_ void* buf = NULL;
size_t buf_size = 0;
struct stat st;
ssize_t k;
FILE *f;
int r;
if (argc != 2) {
log_error("This program requires one argument.");
return EXIT_FAILURE;
}
log_set_target(LOG_TARGET_AUTO);
log_parse_environment();
log_open();
umask(0022);
/* Read pool size, if possible */
f = fopen("/proc/sys/kernel/random/poolsize", "re");
if (f) {
if (fscanf(f, "%zu", &buf_size) > 0)
/* poolsize is in bits on 2.6, but we want bytes */
buf_size /= 8;
fclose(f);
}
if (buf_size < POOL_SIZE_MIN)
buf_size = POOL_SIZE_MIN;
r = mkdir_parents_label(RANDOM_SEED, 0755);
if (r < 0) {
log_error_errno(r, "Failed to create directory " RANDOM_SEED_DIR ": %m");
goto finish;
}
/* When we load the seed we read it and write it to the device and then immediately update the saved seed with
* new data, to make sure the next boot gets seeded differently. */
if (streq(argv[1], "load")) {
int open_rw_error;
seed_fd = open(RANDOM_SEED, O_RDWR|O_CLOEXEC|O_NOCTTY|O_CREAT, 0600);
open_rw_error = -errno;
if (seed_fd < 0) {
write_seed_file = false;
seed_fd = open(RANDOM_SEED, O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (seed_fd < 0) {
bool missing = errno == ENOENT;
log_full_errno(missing ? LOG_DEBUG : LOG_ERR,
open_rw_error, "Failed to open " RANDOM_SEED " for writing: %m");
r = log_full_errno(missing ? LOG_DEBUG : LOG_ERR,
errno, "Failed to open " RANDOM_SEED " for reading: %m");
if (missing)
r = 0;
goto finish;
}
} else
write_seed_file = true;
random_fd = open("/dev/urandom", O_RDWR|O_CLOEXEC|O_NOCTTY, 0600);
if (random_fd < 0) {
write_seed_file = false;
random_fd = open("/dev/urandom", O_WRONLY|O_CLOEXEC|O_NOCTTY, 0600);
if (random_fd < 0) {
r = log_error_errno(errno, "Failed to open /dev/urandom: %m");
goto finish;
}
}
read_seed_file = true;
} else if (streq(argv[1], "save")) {
random_fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (random_fd < 0) {
r = log_error_errno(errno, "Failed to open /dev/urandom: %m");
goto finish;
}
seed_fd = open(RANDOM_SEED, O_WRONLY|O_CLOEXEC|O_NOCTTY|O_CREAT, 0600);
if (seed_fd < 0) {
r = log_error_errno(errno, "Failed to open " RANDOM_SEED ": %m");
goto finish;
}
read_seed_file = false;
write_seed_file = true;
} else {
log_error("Unknown verb '%s'.", argv[1]);
r = -EINVAL;
goto finish;
}
if (fstat(seed_fd, &st) < 0) {
r = log_error_errno(errno, "Failed to stat() seed file " RANDOM_SEED ": %m");
goto finish;
}
/* If the seed file is larger than what we expect, then honour the existing size and save/restore as much as it says */
if ((uint64_t) st.st_size > buf_size)
buf_size = MIN(st.st_size, POOL_SIZE_MAX);
buf = malloc(buf_size);
if (!buf) {
r = log_oom();
goto finish;
}
if (read_seed_file) {
sd_id128_t mid;
int z;
k = loop_read(seed_fd, buf, buf_size, false);
if (k < 0)
r = log_error_errno(k, "Failed to read seed from " RANDOM_SEED ": %m");
else if (k == 0) {
r = 0;
log_debug("Seed file " RANDOM_SEED " not yet initialized, proceeding.");
} else {
(void) lseek(seed_fd, 0, SEEK_SET);
r = loop_write(random_fd, buf, (size_t) k, false);
if (r < 0)
log_error_errno(r, "Failed to write seed to /dev/urandom: %m");
}
/* Let's also write the machine ID into the random seed. Why? As an extra protection against "golden
* images" that are put together sloppily, i.e. images which are duplicated on multiple systems but
* where the random seed file is not properly reset. Frequently the machine ID is properly reset on
* those systems however (simply because it's easier to notice, if it isn't due to address clashes and
* so on, while random seed equivalence is generally not noticed easily), hence let's simply write the
* machined ID into the random pool too. */
z = sd_id128_get_machine(&mid);
if (z < 0)
log_debug_errno(z, "Failed to get machine ID, ignoring: %m");
else {
z = loop_write(random_fd, &mid, sizeof(mid), false);
if (z < 0)
log_debug_errno(z, "Failed to write machine ID to /dev/urandom, ignoring: %m");
}
}
if (write_seed_file) {
/* This is just a safety measure. Given that we are root and
* most likely created the file ourselves the mode and owner
* should be correct anyway. */
(void) fchmod(seed_fd, 0600);
(void) fchown(seed_fd, 0, 0);
k = loop_read(random_fd, buf, buf_size, false);
if (k < 0) {
r = log_error_errno(k, "Failed to read new seed from /dev/urandom: %m");
goto finish;
}
if (k == 0) {
log_error("Got EOF while reading from /dev/urandom.");
r = -EIO;
goto finish;
}
r = loop_write(seed_fd, buf, (size_t) k, false);
if (r < 0)
log_error_errno(r, "Failed to write new random seed file: %m");
}
finish:
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}
int machine_id_setup(void) {
int fd, r;
bool writable;
struct stat st;
char id[34]; /* 32 + \n + \0 */
mode_t m;
m = umask(0000);
/* We create this 0444, to indicate that this isn't really
* something you should ever modify. Of course, since the file
* will be owned by root it doesn't matter much, but maybe
* people look. */
if ((fd = open("/etc/machine-id", O_RDWR|O_CREAT|O_CLOEXEC|O_NOCTTY, 0444)) >= 0)
writable = true;
else {
if ((fd = open("/etc/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY)) < 0) {
umask(m);
log_error("Cannot open /etc/machine-id: %m");
return -errno;
}
writable = false;
}
umask(m);
if (fstat(fd, &st) < 0) {
log_error("fstat() failed: %m");
r = -errno;
goto finish;
}
if (S_ISREG(st.st_mode)) {
if (loop_read(fd, id, 32, false) >= 32) {
r = 0;
goto finish;
}
}
/* Hmm, so, the id currently stored is not useful, then let's
* generate one */
if ((r = generate(id)) < 0)
goto finish;
if (S_ISREG(st.st_mode) && writable) {
lseek(fd, 0, SEEK_SET);
if (loop_write(fd, id, 33, false) == 33) {
r = 0;
goto finish;
}
}
close_nointr_nofail(fd);
fd = -1;
/* Hmm, we couldn't write it? So let's write it to
* /run/systemd/machine-id as a replacement */
mkdir_p("/run/systemd", 0755);
if ((r = write_one_line_file("/run/systemd/machine-id", id)) < 0) {
log_error("Cannot write /run/systemd/machine-id: %s", strerror(-r));
unlink("/run/systemd/machine-id");
goto finish;
}
/* And now, let's mount it over */
r = mount("/run/systemd/machine-id", "/etc/machine-id", "bind", MS_BIND|MS_RDONLY, NULL) < 0 ? -errno : 0;
unlink("/run/systemd/machine-id");
if (r < 0)
log_error("Failed to mount /etc/machine-id: %s", strerror(-r));
else
log_info("Installed transient /etc/machine-id file.");
finish:
if (fd >= 0)
close_nointr_nofail(fd);
return r;
}
int main(int argc, char *argv[]) {
_cleanup_close_ int seed_fd = -1, random_fd = -1;
_cleanup_free_ void* buf = NULL;
size_t buf_size = 0;
ssize_t k;
int r, open_rw_error;
FILE *f;
bool refresh_seed_file = true;
if (argc != 2) {
log_error("This program requires one argument.");
return EXIT_FAILURE;
}
log_set_target(LOG_TARGET_AUTO);
log_parse_environment();
log_open();
umask(0022);
/* Read pool size, if possible */
f = fopen("/proc/sys/kernel/random/poolsize", "re");
if (f) {
if (fscanf(f, "%zu", &buf_size) > 0)
/* poolsize is in bits on 2.6, but we want bytes */
buf_size /= 8;
fclose(f);
}
if (buf_size <= POOL_SIZE_MIN)
buf_size = POOL_SIZE_MIN;
buf = malloc(buf_size);
if (!buf) {
r = log_oom();
goto finish;
}
r = mkdir_parents_label(RANDOM_SEED, 0755);
if (r < 0) {
log_error_errno(r, "Failed to create directory " RANDOM_SEED_DIR ": %m");
goto finish;
}
/* When we load the seed we read it and write it to the device
* and then immediately update the saved seed with new data,
* to make sure the next boot gets seeded differently. */
if (streq(argv[1], "load")) {
seed_fd = open(RANDOM_SEED, O_RDWR|O_CLOEXEC|O_NOCTTY|O_CREAT, 0600);
open_rw_error = -errno;
if (seed_fd < 0) {
refresh_seed_file = false;
seed_fd = open(RANDOM_SEED, O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (seed_fd < 0) {
bool missing = errno == ENOENT;
log_full_errno(missing ? LOG_DEBUG : LOG_ERR,
open_rw_error, "Failed to open " RANDOM_SEED " for writing: %m");
r = log_full_errno(missing ? LOG_DEBUG : LOG_ERR,
errno, "Failed to open " RANDOM_SEED " for reading: %m");
if (missing)
r = 0;
goto finish;
}
}
random_fd = open("/dev/urandom", O_RDWR|O_CLOEXEC|O_NOCTTY, 0600);
if (random_fd < 0) {
random_fd = open("/dev/urandom", O_WRONLY|O_CLOEXEC|O_NOCTTY, 0600);
if (random_fd < 0) {
r = log_error_errno(errno, "Failed to open /dev/urandom: %m");
goto finish;
}
}
k = loop_read(seed_fd, buf, buf_size, false);
if (k < 0)
r = log_error_errno(k, "Failed to read seed from " RANDOM_SEED ": %m");
else if (k == 0) {
r = 0;
log_debug("Seed file " RANDOM_SEED " not yet initialized, proceeding.");
} else {
(void) lseek(seed_fd, 0, SEEK_SET);
r = loop_write(random_fd, buf, (size_t) k, false);
if (r < 0)
log_error_errno(r, "Failed to write seed to /dev/urandom: %m");
}
} else if (streq(argv[1], "save")) {
seed_fd = open(RANDOM_SEED, O_WRONLY|O_CLOEXEC|O_NOCTTY|O_CREAT, 0600);
if (seed_fd < 0) {
r = log_error_errno(errno, "Failed to open " RANDOM_SEED ": %m");
goto finish;
}
random_fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (random_fd < 0) {
r = log_error_errno(errno, "Failed to open /dev/urandom: %m");
goto finish;
}
} else {
log_error("Unknown verb '%s'.", argv[1]);
r = -EINVAL;
goto finish;
}
if (refresh_seed_file) {
/* This is just a safety measure. Given that we are root and
* most likely created the file ourselves the mode and owner
* should be correct anyway. */
(void) fchmod(seed_fd, 0600);
(void) fchown(seed_fd, 0, 0);
k = loop_read(random_fd, buf, buf_size, false);
if (k < 0) {
r = log_error_errno(k, "Failed to read new seed from /dev/urandom: %m");
goto finish;
}
if (k == 0) {
log_error("Got EOF while reading from /dev/urandom.");
r = -EIO;
goto finish;
}
r = loop_write(seed_fd, buf, (size_t) k, false);
if (r < 0)
log_error_errno(r, "Failed to write new random seed file: %m");
}
finish:
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}
static int generate(char id[34]) {
int fd, r;
unsigned char *p;
sd_id128_t buf;
char *q;
ssize_t k;
const char *vm_id;
assert(id);
/* First, try reading the D-Bus machine id, unless it is a symlink */
fd = open("/var/lib/dbus/machine-id", O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
if (fd >= 0) {
k = loop_read(fd, id, 32, false);
close_nointr_nofail(fd);
if (k >= 32) {
id[32] = '\n';
id[33] = 0;
log_info("Initializing machine ID from D-Bus machine ID.");
return 0;
}
}
/* If that didn't work, see if we are running in qemu/kvm and a
* machine ID was passed in via -uuid on the qemu/kvm command
* line */
r = detect_vm(&vm_id);
if (r > 0 && streq(vm_id, "kvm")) {
char uuid[37];
fd = open("/sys/class/dmi/id/product_uuid", O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
if (fd >= 0) {
k = loop_read(fd, uuid, 36, false);
close_nointr_nofail(fd);
if (k >= 36) {
r = shorten_uuid(id, uuid);
if (r >= 0) {
log_info("Initializing machine ID from KVM UUID.");
return 0;
}
}
}
}
/* If that didn't work either, see if we are running in a
* container, and a machine ID was passed in via
* $container_uuid the way libvirt/LXC does it */
r = detect_container(NULL);
if (r > 0) {
char *e;
r = getenv_for_pid(1, "container_uuid", &e);
if (r > 0) {
if (strlen(e) >= 36) {
r = shorten_uuid(id, e);
if (r >= 0) {
log_info("Initializing machine ID from container UUID.");
free(e);
return 0;
}
}
free(e);
}
}
/* If that didn't work, generate a random machine id */
r = sd_id128_randomize(&buf);
if (r < 0) {
log_error("Failed to open /dev/urandom: %s", strerror(-r));
return r;
}
for (p = buf.bytes, q = id; p < buf.bytes + sizeof(buf); p++, q += 2) {
q[0] = hexchar(*p >> 4);
q[1] = hexchar(*p & 15);
}
id[32] = '\n';
id[33] = 0;
log_info("Initializing machine ID from random generator.");
return 0;
}
